Former New York City Mayor Rudy Giuliani has openly questioned whether President Barack Obama actually "loves America" - or even the people in it.

The 70-year-old politician directly challenged Obama's patriotism on Wednesday night while speaking in front of the 2016 Republican presidential contender and about 60 right-leaning business executives and conservative media types, Politico reported.

"I do not believe, and I know this is a horrible thing to say, but I do not believe that the president loves America," Giuliani said during a private group dinner for Wisconsin Gov. Scott Walker at the 21 Club, a former Prohibition-era speakeasy in midtown Manhattan.

"He doesn't love you. And he doesn't love me. He wasn't brought up the way you were brought up and I was brought up through love of this country."

Obama's weak foreign policy decisions and questionable public remarks when confronting terrorists were also criticized by Giuliani, according to TIME.

The president "sees our weaknesses as footnotes to the great things we've done."

"What country has left so many young men and women dead abroad to save other countries without taking land? This is not the colonial empire that somehow he has in his hand. I've never felt that from him. I felt that from [George] W. [Bush]. I felt that from [Bill] Clinton. I felt that from every American president, including ones I disagreed with, including [Jimmy] Carter. I don't feel that from President Obama."

"You've got to be able to criticize Islam for the parts of Islam that are wrong. You criticize Christianity for the part of Christianity that is wrong. I'm not sure how wrong the Crusades are. The Crusades were kind of an equal battle between two groups of barbarians. The Muslims and the crusading barbarians. What the hell? What's wrong with this man that he can't stand up and say there's a part of Islam that's sick?" he said, referring to the president's remarks from the National Prayer Breakfast earlier this month.

"With all our flaws we're the most exceptional country in the world. I'm looking for a presidential candidate who can express that, do that and carry it out," the former mayor said about Walker, who is currently considering his own run for the White House.

"And if it's you, Scott, I'll endorse you. And if it's somebody else, I'll support somebody else," he said, adding that he would "eventually" back a Republican presidential candidate.

On Tuesday, Walker also slammed Obama while dismissing criticism that he dropped out of college, Yahoo News reported.

"That's the kind of elitist, government-knows-best, top-down approach we've had for years," Walker told Fox News' Megyn Kelly. "We've had an Ivy-trained lawyer in the White House for six years who's pretty good at reading off the TelePrompter but has done a pretty lousy job leading this country."

Meanwhile, Giuliani refused to back off his comments on Thursday's "Fox & Friends," clarifying his criticism of Obama.

"What I'm saying is, in his rhetoric I very rarely hear the things that I used to hear Ronald Reagan say, the things that I used to hear Bill Clinton say about how much he loves America. ... I do hear him criticize America much more often than other American presidents. And when it's not in the context of an overwhelming number of statements about the exceptionalism of America, it sounds like he's more of a critic than he is a supporter," he said.